Corrosion and Wear performances analysis of PVD CrMoN/Cr Coatings

Tools coated CrN based alloys are currently used in several industries for machining and manufacturing, but present severe wear, limiting their service life. Seeking an alternative, three CrMoN monolayers (~1µm in thickness) coatings with varying in the Mo percentage content were elaborated using the RF magnetron co-sputtering method. These coatings were evaluated and compared with the alloy currently used (CrN) by electrochemical tests in NaCl solution (stationary and no stationary method) and sliding wear tests (ball-on-disc configuration) performed at room temperature. The results indicate that the samples coated with CrMoN presented better performance against wear and corrosion than the uncoated sample. Among the coatings, the labeled C1 (27 % Mo) showed the best corrosion resistance as it presents a positive corrosion potential Ecorr. However, the best wear resistance (lowest coefficient of friction) was shown by coating labeled C4 (33 % Mo). All of the tested specimens underwent abrasive wear in addition to adhesive wear

Mineral Analysis of Some Local Cultivars of Melon (Cucumis melo L.)

Abstract: Twenty six cultivars of which twenty four local and two introduced (Yellow canary and Lobnani) were evaluated. In order to study the physicochemical quality of melon, a mineral analysis was carried out. This analysis included sodium, potassium, phosphorus and calcium plus magnesium. Na and K were measured by photometer with flame, phosphorus was determined by spectrophotometer and Ca ++ -Mg ++ were proportioned by a proportioning colorimetric. The result showed that all cultivars exhibited the highest level for Na. K content was higher than 2% in 60% of cultivars. P content was higher than 0.1 % in 70 % of cultivars. Ca ++ -Mg ++ content was higher than 1 meq/l in 50% of cultivars. Analysis of variance and hierarchical classification, according to variations in mineral element between cultivars, were assured with SPSS 12.0. Analysis of variance confirmed significant differences (p < 0:05) between the different cultivar for every parameter

Characterization of Several Local Cultivars of Watermelon Collected from Arid Region in Tunisia

Abstract: This study reports on the analysis of 8 local watermelon cultivars (Citrullus lanatus (Thumb)) collected in the South of Tunisia which were compared to two introduced watermelon cultivars widely-grown in this arid area. The analysis was based on the characterization of fruits. The Principal Component Analyze (PCA) showed that the three modern cultivars constitute a distingue group specified by their lower weight fruit and their relatively high fructose and glucose contents. However, it was found that the eight local cultivars was more variable and its belong to two diverse groups. This study clearly shows the need to safeguard and manage this precious local germplasm both ex situ and in situ, as this material may contain valuable genes for future breeding activities and also future cultivation practices